Lagoons under the microscope

At the Ria de Aveiro Lagoon in Portugal the day starts early for European scientists as they set out to gather samples.

The lagoon offers a rich but fragile 75 square kilometre ecosystem of wetlands, seagrasses and salt marshes used as nursery areas for bivalves, crustaceans, fish and birds.

It is a natural treasure that, as with other European coastal lagoons, is facing huge threats.

“Among the most common problems we find here is the high presence of nutrients in the water. These nutrients favour the bloom of green algae. The green algae absorb oxygen from the water, and eventually the whole aquatic ecosystem can lose its environmental health and quality. These last years we have also found a new trend of pollutants, chemical compounds from drugs and other nanoparticles, that can also challenge the quality of the environment around,” explained Ana Lillebø a biologist and project coordinator at the University of Aveiro/Lagoons.

Climate change could also pose dangerous threats. It could alter volumes of water in the lagoon, the temperature and acidity, which could then weaken further an already delicate ecosystem. Researchers want to know how key vegetable and animal species in the lagoon’s trophic chain would react to sudden changes in their ecosystems.

“We can predict the future climate change patterns with models. And if we match those models with our biological research, we can foresee how these crucial species will evolve over time; if they will increase, decrease or if they will simply disappear from the lagoon’s ecosystems,” said Arnaldo Marín Atucha an ecologist at the University of Murcia

This scientific effort, part of a European Union research project, includes detailed field work in four coastal lagoons around Europe, each with different realities and challenges but with a common urgency in the need to protect them. Biological data is matched with sophisticated computer modelling.

Researchers try to predict using interactive maps how climate change-induced alterations, but also pressure from tourism, industry or agricultural land use, will affect the lagoons’ health and sustainability.

Per Stalnacke is a water quality expert at the Norwegian Institute for Agricultural and Environmental Research and pointed out: “Of course there is a large uncertainty. But we have to remember that we are collecting the best available scientific knowledge into these computer models. So this is not science fiction”.

The research also involves dealing with the local population. Scientists organise focus groups with hunters and fishermen to provide scientific information and receive factual data and meaningful feedback on the lagoon’s real potential and also its main weaknesses.

“We provide them with maps basically. And we asked them to use dots and colours to show us on those maps which areas of the lagoons they feel are developing well and which areas they feel are being threatened. So besides getting information about which issues there are at stake, we also get the geographic location of them,” explained Geoffrey D. Gooch, Professor of Water & Environmental Policy at the University of Dundee.

It is a three year research effort that scientists, hunters and fishermen hope will help to preserve some quite unique natural ecosystems. A point underlined by Boaventura Bastos Marrafa, President of the Avanca Hunting & Fishing Association.

“We have the sea, then the sea inlet, then the lagoon. And then, nothing else except lots of motorways. There is no more space for wildlife. So all hunting friendly-spots around this area are in the lagoon. That is why we, hunters, also have to fight to protect it, and preserve the natural balance of these ecosystems.”

Arnaldo Marín Atucha, an ecologist at the University of Murcia concluded: “Each lagoon is unique. If we lose this natural heritage, we will also lose a bit of our own identity”.